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9

To elaborate on @Majenko's answer, both SGMII and 1000Base-x are dual 1000Mbps SERDES pairs (one in each direction), at least until the 1000Base-X signals reach the optical transceiver. The main difference is in the auto-negotiation capabilities. In 1000Base-X, auto-negotiation is limited to flow-control (and duplex, which is not really used since it's ...


9

USB is hot-pluggable, so you don't actually have to power down to remove/insert those (I don't know about HDMI though, so I'd keep powering down). From an ELECTRICAL/ELECTRONIC/SOFTWARE standpoint there is NO problem with doing this. None of the equipment or the operating systems care. From a MECHANICAL standpoint, you are adding wear and tear to the ...


8

If you're doing this literally every day, you really should invest in a keyboard-video-mouse (KVM) switch. Here is just one example.


7

To compile programs for the ATmega you need a so called toolchain. A well used one is the GNU AVR toolchain (and it is FLOSS). Linux (best), Mac and Windows can handle it. To get the compiled code into your microcontroller, you need a programmer like AVRdude. The corresponding hardware is called an In-System-Programmer (ISP). There are a lot of projects out ...


6

Most Ethernet systems are made up of a number of building blocks. The two most important are the Ethernet MAC Device (the device that actually makes and receives Ethernet frames), and the Ethernet PHY (PHYsical interface) device - the device that connects you to your wires, fibre, etc. These two devices are connected using a Media Independent Interface (...


5

First of all, it should be noted that RTS/CTS referred to in the question have nothing to do with hardware wires such as the RTS/CTS wires frequently used for UART handshaking. That having been said, this is a low-level radio-communication problem and would appear to be about as topical here as would be questions about things like XBee. The "hidden/exposed"...


5

'retiming' logic usually refers to inserting pipeline stages to make timing constraints. From your description, some of the pipeline stages are made optional controlled by this parameter. If you can't close timing in the area of this core, enable it.


5

Look into Project HiJack, which establishes 2 way serial connection to the iPhone via the earphone port and harvests power! The source code is open source. They use Manchester encoding for modulation, a brief analysis of their code is on my blog.


4

The Atmel AVR Studio tools include an assembler and C compiler, and only run under Windows. A debugger and simulator are available. I'm using Studio 5 on a Win7 x64 laptop. Studio 5 is available here: http://www.atmel.com/tools/ATMELAVRSTUDIO.aspx Operating systems aren't usually used with microcontrollers like the 8-bit AVR. You typically write your code ...


4

Typically, a set of MII lines are connected from the MAC to a single PHY. The reason for multiple addresses for MDIO is for SOCs that contain multiple MAC modules and for switch chips. The MII from each MAC module connect to its PHY. However, to save pins on the SOC, there will be only one set of MDIO pins. The MACs will share these lines communicating with ...


3

Use the inverse ARP protocol. See http://en.wikipedia.org/wiki/Address_Resolution_Protocol#Inverse_ARP_and_Reverse_ARP . I don't know if the module you are using can do this, or if you will have to do this yourself. The basic idea is to send an Ethernet packet to the MAC address in question with the 8 in the OPER field. The device at the other end should ...


3

You're not really missing anything. Some organizations release only a handful of bespoke automation devices (often reflashing a generic OEM MAC), while some are full OEMs, launching high-volume products. Finally, some organizations are both, and may have budgeting requirements that make it easier to purchase an IAB for a project/product line, than to ...


3

MII MAC Mode This mode will be used when you want to connect MAC(Media Access Control) Devices which have inbuilt Ethernet Interface Control like Processor(say iMX28), Controller(say AT91SAM).These are capable to taking the data for processing and using it for different purposes.Other case is cascading i.e. connecting two or more KSZ8863RL together for ...


3

Find a switch/PHY chip that has dual (R)MII interfaces. For example: http://www.farnell.com/datasheets/2175960.pdf. One MII to the compute module, the second RMII to the microcontroller and you have 2 ports left that you can connect to regular magnetics and bring outside.


2

Have you given Upverter a try? It has a mac app as well as runs in the browser so you can try it out without installing anything. [I work at Upverter]


2

I've found that DigiKey's SchemeIt editor online works quite well, with export to PDF and PNG. I wish that there was an agreed-upon exchange format for schematic diagrams, so that circuits could be moved easily from one schematic capture tool to another. I use Eagle CAD for board design, but their schematic capture tool is awkward and produces ugly ...


2

Depending on your needs, Arduino may be a fun starter kit with lots of shields (hardware expansions) available and a huge community. Arduino has a low entry level from both a hardware and software respective and you can still write regular C/C++ with it. However, Arduino doesn't have a debugger. Recently Atmel has released AVR Studio 5, which is integrated ...


2

I use the gcc/AVR toolchain under OS-X, inside eclipse and from the command line. I don't know what other gcc code-generation options are available, but it would surprise me if gcc didn't target most of the more popular devices.


2

I suggest you to install LTSpice IV into Wine, it is not graphically pleasing, but after hours of fiddling with MacSpice I got to say that LTSpice made my day :)


2

Here are few pointers: SSDP UPnP Fing or equivalent tool. Also, Lantronix has a protocol for discovering their embedded devices, you might want to look there.


2

MDI is a type of Ethernet port connection using twisted pair cabling. The MDI is the component of the media attachment unit that provides the physical and electrical connection to the cabling medium which is used to connect network devices (hubs and switches) with other hubs and switches without the use of a crossover cable or null modem. Where MII is Media ...


2

SPICE netlists are just text files, so open in any editor that you have available. I suggest BBEdit, or Nano on the command list or even preview.


2

This is a general networking question, not limited to any microcontroller. The reason you can see the arp cache (the mapping between IP and MAC addresses) on your RPi or any other computer is that they've presumably been on for a while, have heard ARP responses from other machines on the network, and have cached them. Let me rephrase your question: absent ...


2

Many older Ethernet PHYs do not support auto-mdix. Therefore the first thing I would try is changing the cable. If your current cable is straight through try a crossover, if your current cable is crossover try a straight through cable. If that doesn't help then I would try looking at what speed and duplex mode they negotiate with the PC. In particular is ...


1

MAC Functions: Physical addressing (MAC addressing) LAN switching (packet switching), including MAC filtering, Spanning Tree Protocol (STP) and Shortest Path Bridging (SPB) Data packet queuing or scheduling Store-and-forward switching or cut-through switching Quality of Service (QoS) control Virtual LANs (VLAN) PHY functions: Bit-by-bit or symbol-by-symbol ...


1

MII, GMII, RGMII, XGMII, XAUI, etc. are all MAC to PHY interfaces. They all serve a similar purpose, but have slightly different characteristics. MII = 4 bit parallel for 100M, RMII = 2 bit parallel for 100M, GMII = 8 bit parallel for 1G, RGMII = DDR 4 bit parallel for 1G, XGMII = DDR 32 bit parallel for 10G, XAUI = 4x3.25 Gbps serial for 10G. PHY to PHY ...


1

I'm not familiar with LTSpice, I use a different simulator (Cadence Spectre) but there I can also not plot Vt directly. The reason for this is that Vt is an internal model parameter. In Spectre I can get a value for Vt at a certain operating point, for that I need to do a DC operating point simulation so not a DC sweep ! If I do multiple of these operating ...


1

There are PHYs with RGMII, SGMII and MDI. In these case RGMII connect to MAC. SGMII connect to a media module, such as SFP module which can be fiber or copper. MDI as usual for Copper Transformer interface. In some PHY the link to MAC is over SGMII.


1

Do you mean links such as the Wikipedia articles for Fast Ethernet (100 Mb/s) and Gigabit Ethernet (1 Gb/s)? They seem to be rather complete to me as far as the kinds of questions you're asking. Yes, Gigabit Ethernet (1000base-T) requires all four pairs in each link.


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